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Патент USA US3027256

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United States Patent ()?lice
Patented Mar. 27, 1962
and, (5) be non-metallic since metals in general adversely
Philip Lee Bartlett, Wilmington, Del., assignor to E. I.
du Pont de Nernours and Company, Wilmington, Del,
a corporation of Delaware
No Drawing. Filed Nov. 3, 1958, Ser. No. 771,215
9 Claims. (Cl. 44-66)
combustion deposits, and, tend to embrittle alloys used
for turbine engines.
De?cient in at least one of the above requirements are
the polar compounds suggested heretofore; compounds
such as metal or ammonium (including quaternary am
monium) salts of inorganic and organic acids (including
acids of phosphorus, sulfur ‘and carboxylic acids) are
This invention is directed to the treatment of hydro
representative of such polar compounds. For example,
Rogers, McDermott and Munday, “Static Electricity in
carbons, such as the distillate fuels, which tend to ac
Petroleum Products,” Oil and Gas J. 55, 166-95 (1957),
cumulate potentially hazardous electrostatic charges in
service. Acording to the present invention, the addition
affect fuel stability and contribute to the formation of
disclose that “all the additives studied so far are polar
compounds which are surface active and promote the
of a hydrocarbon-soluble betaine to a static-prone hy 15 formation of emulsions when the blends are mixed with
drocarbon substrate minimizes the accumulation of static
water. Thus, they fail to meet the water tolerance spe
electricity in such substrate.
ci?cations of jet fuels and in adition are rather easily
The accumulation of electrical charges in the handling
extracted on contact of the fuel with water.”
of hydrocarbons is widely recognized as a serious hazard.
it is an object of the present invention to provide novel
A number of explosions and ?res that have occurred in 20 antistatic ‘agents which are signi?cantly effective, in liquid
recent years during the bulk handling of distillate fuels
hydrocarbons, in minimizing the accumulation of static
and solvents have been attributed to the accumulation
electricity in both types of charge-prone liquid hydrocar
(and subsequent discharge) of static electricity in the
bons. It is a further object of this invention to provide
systems involve-d.
novel liquid hydrocarbon compositions containing anti
Some handling conditions that con
tribute to the rapid generation of dangerous charge levels 25 static agents which antistatic agents do not adversely af_
are rapid flow of fuel through pipelines and hoses, splash
fect other fuel properties such as water tolerance char
?lling of receiving vessels (storage tanks and seagoing
acteristics. It is still another object of the present inven
tankers), and, mixing of the fuel with water.
tion to provide novel liquid hydrocarbon compositions
The problem of static formation in the distillate fuels
containing ‘antistatic agents, said liquid hydrocarbon being
is of considerable concern to the military as well as to 30 a jet fuel and said antistatic agent, in addition to minimiz
the petroleum industry, and much searching has been
ing the accumulation of static electricity, minimizing the
and is being done to ?nd a solution thereto. The results
of a number of investigations indicate that most distillate
fuels would be expected to produce substantial amounts
adverse effects of thermal stress on jet fuels, which ad
of static electricity under service conditions, and prac
tically all produce su?icient static electricity to ignite
vapor-air mixtures, providing there is present a mecha
nism for collecting ‘and discharging the electricity. The
production of static electricity in such fuels is associated
with the presence of colloidal impurities which are ionic
or which are capable of becoming ionized in the hydro
carbon environment.
These impurities are believed to
verse effects are normally encountered.
These and other objects will be apparent in the fol
I lowing speci?cation and claims.
More specifically, the objects of the present invention
are achieved by employing a hydrocarbon-soluble betaine,
as hereinafter described and claimed, as the antistatic
agent in small quantity su?icient to minimize the tendency
of the hydrocarbon to accumulate electrostatic charge.
Such quantity will usually be in the range of from about
0.1 to 30 lbs. per 1000 barrels (0.000033 to 0.01% by
be either naturally occurring or represent fuel degrada
weight) of the static-prone liquid hydrocarbon. It is
tion ‘and oxidation products or residues from treating
preferred ‘to use an antistatic quantity of at least 0.5 lb.
operations. As a result of preferential adsorption of
‘and not more than 15 lbs. per 1000 barrels.
positively or negatively charged ions from the impurities
Betaines which may be used according to this inven
on thec ontainer (e.g. wall or hose lining), the fuel will
tion are hydrocarbon-soluble members of the class of di
acquire a charge of the opposite sign. The rate of pro
duction of static electricity in liquid hydrocarbons in~
polar ions represented by Formula I which follows:
creases with the flow rate and is accelerated by the pres 50
ence of small amounts of water, air and dispersed solids.
Since leakage of the charge from the body of the hy
drocarbon is normally a very slow process, a potential
where R, is a divalent hydrocarbon radical, such ‘as an
may soon be established during the normal handling of
the fuel to ignite fuel-air mixtures or to cause submerged 55 alkylene or alkylidene radical, R2 and R3 are aliphatic
explosions within the fuel when the electricity ?nally dis
charges. The problem is particularly acute with jet fuels.
hydrocarbyl radicals, such as the loWer-alkyl radicals,
and R4 is an uncharged aliphatic radical such as hydro~
As ‘discussed in “Electrostatics in the Petroleum In
dustry,” edits/.1 by A. Klingenberg and J. L. van der
carbyl and hydrocarbyl substituted by ether (—-O—), hy
droxyl (—OH) and carbonyl (—C=O—) groups. R,
apparatus, blanketing of the fuel with inert gases, and
mechanical modi?cations in the handling procedures are
substituents that promote the emulsi?cation of the fuel
with water. To have su?icient hydrocarbon-solubility
the betaine should contain at least about 11 carbon atoms
and preferably at least about 16 carbon atoms in the
Nenne, Elsevier, 1958, expedients such as grounding the 60 is primarily a solubilizing group and should be free of
helpful but not entirely satisfactory safeguards.
most promising approach ‘appears to be the use of addi
tives. To be practical, particularly for use in jet fuels 65 molecule. Ordinarily the betaine will contain no more
than about 35 carbon atoms, and usually up to about
where stringent speci?cations have to be met, an antistatic
30 carbon atoms.
additive should (1) be effective, in technically feasible
Preferably, R1 will be an alkylene radical, particularly
small concentrations, in fuels of both charge types i.e.
methylene, or an alkylidene radical having up to 17 car
in positive prone and negative prone fuels; (2) have no
adverse effect ‘on water-tolerance characteristics of the 70 bon atoms, such as ethylidene, propylidene, undecylidene,
tridecylidene and heptadecylidene.
fuel (3) have no adverse effect on jet fuel thermal sta
R2 and R3 may be the same or different C1-C5 alkyl
bility; (4) have no adverse effect on fuel storage stability;
radicals, e.g. methyl, ethyl propyl, butyl and amyl,
preferably C1-C3.
carbon media to the extent of at least about 0.1 lb.,
preferably at least 0.5 lb., per 1000 barrels (bbls.) of
the hydrocarbon. The quantity of the antistatic agent
needed to minimize the accumulation of static electricity
in the hydrocarbon substrate will vary with the particular
Preferably, R4 is an aliphatic hydrocarbyl radical con
taining up to 20 carbon atoms and may be saturated. or
unsaturated, straight chain or branched chain. Repre
sentative examples of R4 are methyl, butyl, hexyl, decyl,
betaine and the particular liquid hydrocarbon product,
dodecyl‘, tridecyl, octadecyl, octadecenyl, octadecadienyl,
and, will depend, in general, on how prone such hydro
carbon is to accumulate static electricity. Normally, from
about 0.5 to 15 lbs.‘ of additive, and preferably 1 to 15
alkoxypropyl radical.
10 per 1000 bbl. of substrate will be employed. Larger
quantities, e.g. 30 lbs/1000 bbl. are operable for anti
static effects, but are usually unnecessary, also such
unduly large quantities tend to promote the water emulsi
?cation of distillate fuels. While smaller quantites, e.g.
where R is an aliphatic hydrocarbyl radical as de?ned
for R4 above, that is, it may be for example an alkyl, 15 0.1 lb./l000 bbls., may also beoperable, they do not
always provide thedesireddegree. of protection.
alkenyl, or alkadienyl radical having up to 20 carbon
It should be understood that the presence of the anti
atoms, preferably one having 10 or more carbons.
static agent in the hydrocarbon substrate does not do
Also, R4 may be a hydrocarbon radical containing a
away with the need for adequate grounding of the equip
carbonyl group, as in
20 ment for containing and handling the hydrocarbon prod
and 3,7-dimethyl-2,6-octadienyl. Also, R4 may be an
hydroxy-alkoxy-alkyl radical, such as a 2-hydroxy-3
where R is as de?ned above.
The antistat apparently functions to minimize the
accumulation of static electricity in the hydrocarbonprod
not by conducting the charge (as it tendsto buildup
in the hydrocarbon) from the hydrocarbon to the ground
The preferred betaines
may be represented generically by Formula II which
25 ing means.
The use of the betaine antistatic. agents of the present
invention is applicable to any liquid hydrocarbon that
boils in the distillate fuel range and is prone to accumu-v
late static electricity in service.
These include hydro
where x=0 or 1 andRl, R2, R3 and R are as preferential 30 carbon solvents -and distillate fuels, representative ex
amples of which are the solvent naphthas, Varsols and
ly de?ned above. The “R” groups and x may be varied
Stoddard solvent, isooctane, both raw and re?ned kero
in accordance with the above de?nition so that the hydro~
sines, gasoline (both automotive and aviation), jet fuels
carbon content of the dipolar ion is su?icient for solu
(JP-4, JP-S and LIP-6), diesel fuel and heating oil. The
bilization of a substantial quantity of the compound in
the hydrocarbon to be treated; that is, the compound 35 problem appears to be particularly acute with the jet
fuels; accordingly, the preferred embodiment of the in
should contain from about 11 to about 35 carbon atoms.
vention is the use of the instantly described and claimed
The following are representative betaines of the pres
antistatic additives in jet fuels.
ent invention in which R; of Formula I is an ‘aliphatic
For convenience in handling, the betaine antistatic
hydrocarbyl radical attached to nitrogen of a dialkyl
agents may be added to the hydrocarbon substrateas a
glycine radical: N-lauryl betaine (i.e. N-lauryl-N,N-di
concentrate in a suitable carrier, which is preferably a
methyl glycine), N-hexadecyl betaine, N~octadecyl be
liquid hydrocarbon. For example, a 20 to 60%, usually
taine, N-octaclecenyl betaine, N-lauryl-N,N-dipropyl
about 50%, by weight of N-lauryl betaine in xylene or
glycine, C-decyl betaine (i.e., 2-trimethylammonio-do
decanoate)‘, C-dodecyl betaine, C-tetradecyl betaine; and,
kerosene is a preferred form of the antistatic additive.
The antistatic additives may be used in the presence
N-‘lauryl-C-methyl betaine. The above betaines are de 45
of other additives that the hydrocarbon product may nor
scribed and may be prepared by methods disclosed by
mally contain, such as the approved oxidation and rust
Downing and Johnson in U.S. Patent 2,129,264.
inhibitors for the jet fuels.
Other betaines which may beused according to this
The betaines of this invention are effective antistatic
invention are those in which R, is an aliphatic substi
tuted hydrocarbyl radical, e.g. ROCH2CHOHCH2-— of 50 agents in practical use concentrations. They are ashless
(i.e. being non-metallic they leave no. harmful residues
Formula II, attached to nitrogen of an N,N-dialkyl gly
in the combustion of fuels containing them) and in gen
cine. Representative examples are N-(2-hydroxy-3-butyl
eral do not promote the tendency of the fuel blends con
oxypropyl)betaine, N-(2-hydroxy-3-decy l oxypropyl)be
taine, N-(2-hydroxy-3-lauryloxypropyl)betaine, N-[2-hy
droxy-3 - (3,7 _ dimethyl - 2,6 - octadienyl)oxypropyl]be
taine, N-(2-hydroxy-3-tridecyloxypropyl)betaine, N-(2
hydroxy-3 - octadecenyloxypropyl) - N,N - diethyl glycine
and the correspondingly substituted -N,N-dipropyl gly
taining them to emulsify when mixed with water. This
is particularly "surprising and important since betaines in
general are regarded as surface active agents and it is
known that polar additives that are surface active, when
used in concentrations required for antistatic activity,
have the major disadvantage of failing to meet the water
The above N-(2-hydroxy-3-alkoxypropyl)-N,N-dialkyl 60 tolerance speci?cations of fuels such as the jet fuels.
As shown in the examples, jet fuel containing N-lauryl
betaine as an antistat not only passes the standard water
ample by condensing an'alcohol with epichlorhydrin and
tolerance test, but shows no tendency to accumulate elec
reacting the intermediate condensation product thus ob
glycines may be prepared by known methods, for ex
trostatic charge even after the blended fuel has been
tained with an alkali metal salt of an N,N-dialkyl glycine.
Preferably, the alcohol will contain from 10 to 20 carbon 65 shaken with as much as 5 vol. percentof water. Fur
ther, as shown in the examples, N~lauryl betaine, in anti
atoms. Available alcohols of this type are the “Lorol”
stat concentration, is very elfective to minimize the de
fatty alcohol mixtures, e.g. “Lorol” 5 which contains
alcohols having from 10 to 18 carbon atoms with lauryl
terioration of jet fuel when the blended jet fuel is sub
jected to the thermal stresses of the CFR Coker Test.
alcohol predominating; “Ocenol” fatty alcohols, e.g.
“Ocenol” P which is principally oleyl alcohol; geraniol 70 Thev following representative examples illustrate the
present invention.
(3,7-dimethyl-2,6-octadienol); oxo-alc'ohols, which are
mixtures of branched chain primary alkanols, e.g. oxo—
Testing of the betaine antistatic agents was conducted
As illustrated above, R, R1, R2, R3 and x will be
by the procedure described by Rogers et al.', Oil and Gas
chosensosthat the dipolar ion will be soluble in hydro
Journal, 55, 166-95v (1957.). The equipment employed
was essentially a duplicate of that described in the above
reference ‘and was enclosed in a constant humidity
The tests involve recirculating a sample of the liquid
identical results in the electrostatic and water tolerance
hydrocarbon (with or without additive) at a ?ow rate of
ing example.
Substantially similar results are obtained on employ
ing other betaines of this type, as indicated in the follow
1450 rah/minute through a column packed with Pyrex
Example 2
By the procedure of Example 1, Fuels A and B de
glass wool (Filtering Fiber Cat. No. 800). The glass
wool acts as a charge separator. A tungsten wire elec
trode inserted into the packed column leads to an external
scribed above were treated to contain N(2-hydroxy-3
. octadecyloxypropyl) betaine in the concentrations given
spark gap, which provides the means for discharging the
accumulating static electricity. The humidity of the at
mosphere contained in the Lucite enclosure for the whole
below, and the resulting blends tested to yield the follow
ing results:
apparatus was maintained at 15% or less, to minimize
the eifect of moisture on the conductivity of the air
through which the spark gap ?res. In the present runs
the fuel was circulated (and recirculated) through the
glass wool packed column for a 10 minute warm‘up
period, and then a 20 minute run was made during which
2-kv. Discharges in 20
Additive Cone, lbs/1,000 bbl.
Fuel A
time the number of discharges were counted across the
spark gap which had been calibrated to ?re at 2000 volts 20
(2 kv.). The number of 2 kv. discharges in 20 minutes
is a measure of the tendency of the fuel to accumulate
static electricity and thus is a measure of the e?ectiveness
None (Control) ............................. __
7.5 __________________________________________ __
15 ___________________________________________ -_
Fuel B
All the fuel blends passed the water tolerance test.
of the antistatic additive.
In addition, each fuel (with and without additives)
Exacple 3
was subjected to the water tolerance test in accord with
A 50 weight percent solution in xylene of a betaine
of the formula:
Method 3251 of Federal Speci?cation VV—L—79lc. The
test consists of shaking 80 ml. of the fuel and 20 ml. of
water (containing a pH 7 phosphate buffer) in a 100 ml.
stoppered graduate cylinder for 2 minutes, and allowing 30
To pass the test, the water
was blended by stirring into liquid hydrocarbon products
and oil phases must break cleanly within the 5 minute
standing period. Any emulsion or lace in the oil, or
B and C described in Example 1. R and R1 of the beta
1ne, the concentrations of betaine employed, and the
it to stand for 5 minutes.
preciiptate at the interface leads to a “fail” rating.
results of the electrostatic test are as described below:
Example 1
A 50 weight percent xylene solution of N-(Z-hydroxy
in 20 Minutes
Additive, lbs/1,000 bbl.
7. 5
Cone, lbs/
1,000 bbl.
None (Control) _____________________________ --
Hydrocar- Hydrocar
bon B
No. of 2-kv. Discharges 45
No. ZMkY. ultftischarges
es’ m
3-“octadeceny1"—oxypropyl) betaine was blended by stir
ring into a liquid hydrocarbon product as designated be
low, to provide the concentration of the active ingredient 40
also given below. The results obtained in the circulating
static electricity test on the treated and untreated hydro
carbons follow:
bon D
lauryl __________ _. —CH2-—_..___._
octadecyl ______ __
-—Cl-I2— _____ __
__ dec_vlCH<..___
methyl _______ __
_ positive.__
H) Gasoline1 __________________ _- negative-.
All the hydrocarbon blends passed the water tolerance
Example 4
The procedure of Example 3 was repeated, employing:
1A leaded automotive-type gasoline containing 3 ml. of
tetraethyl lead per gallon.
All the above compositions passed the water tolerance 60
at a concentration corresponding to 15 lbs/i000 bbl.
(This betaine was prepared by reacting n-dodecyl alpha~
The results of the electrostatic test show that the
chloroacetate with the sodium salt of N,N-dimethyl gly
betaine effectively minimizes the accumulation of static
cine.) The results ot‘ the antistatic test in hydrocarbons
electricity (being completely eiiective at the 15 lb./1000
bbl. level) in liquid hydrocarbon products, irrespective of
the charge sign the hydrocarbon may acquire.
The N(2-hydroxy-3~“octadecenyl”-oxypropyl) betaine
l3 and D were as follows:
The number of 2-kv. discharges in 20 minutes was re
duced from 720 to 140 in positive'prone Fuel B, and
from 459 to 19 in negative~prone Fuel D. Both com
of this example was prepared by reacting “Ocenol” P
positions (containing the betaine) passed the water toler
fatty alcohol with epichlorhyclrin in the presence of sul
furic acid catalyst, followed by reacting the thus-produced 70 ance test.
Example 5
octadecenyl glyceryl ether chloride with sodium N,N-di~
methylglycinate in the presence of KI catalyst.
A re?ned kerosine, with and without N‘lauryl betaine
Employing the corresponding N(2-hydroxy-3-octa
decenyloxypropyl)-N,N-diisopropyl glycine, at a concen
at a concentration corresponding to 1 lb./ 1000 bbl., was
vigorously shaken with 0.1 and 5 volume percent of
tration of 15 lbs./ 1000 bbl. in Fuels A and B above, gave 75 water for about 5 minutes and the mixtures allowed to
settle for 16 hours. The electrostatic test results on the
obtained at room temperature using a platinum ring
coated with polythene.
thus-treated products follow:
N-Lauryl Betaine Present
in 20
lbs. /l,000
7. 5
7. 5
0. 1
The results show that fuel containing N-lauryl betaine
(1 lb./ 1000 bbl.) resists accumulating static electricity
40. 7
36. 7
31. 5
35. 6
31. 6
26. 4
It is currently believed that an additive cannot reduce
the interfacial tension between fuel and Water below 15
even after being contacted with water.
dynes/em. without interfering with the operation of fuel
water separators. Thus, the above results indicate N
l‘auryl betaine, at concentrations that are effective for
This example shows the bene?cial effect of N-lauryl 20 antistatic use, should not cause di?iculty in the separation
betaine on jet fuel ?lterability and pre-heater tube de
of fuel from water.
posits as determined in the CPR Coker Test, in ac
It will be apparent that many widely different embodi
cordance with CRC Manual No. 3, Instructions for
ments of this invention may be made without departing
Operation and Maintenance of CPR Fuel Coker, March
from the spirit and scope thereof, and therefore it is
1957, of the Coordinating Research Council, Inc. (The 25 not intended to be limited except as indicated in the ap
fuel coker is a laboratory apparatus designed to measure
pended claims.
the fuel’s high temperature stability. In principle, it sub
I claim:
jects the test fuel to the same level of temperature stress
1. A liquid hydrocarbon boiling in the distillate fuel
and in a manner similar to that occurring in jet engines.)
range containing an antistatic quantity, of from 0.1 to
The results obtained with two LIP-4 jet fuels-one 30 30 pounds per 1000 barrels of said hydrocarbon, of a
Example 6
relatively stable (Fuel F) the other relatively unstable
hydrocarbon-soluble betaine of the formula
(Fuel G)—-are tabulated below. The following code was
used to rate each inch of the preheater tubc’s 13 inches
of length:
0——No visible deposits
1—Visible haze or dulling, but no color
2—Barely visible discoloration
3—-Light tan to peacock stain
4—-Heavier than 3
wherein R1 is a saturated divalent hydrocarbon radical,
R2 and R3 are saturated aliphatic hydrocarbon radicals,
40 and R4 is an uncharged aliphatic radical taken from the
group consisting of hydrocarbon radicals and ether oxy
Preheater ° F
Filter ° F
gen-, hydroxyl-, and carbonyl-substituted hydrocarbon
radicals, R4 being free of substituents that promote the
emulsi?cation of said liquid hydrocarbon with water, said
Flow rate, lbs/hr
Pressure, lb
betaine containing from about 11 to about 35 carbon
Minutes to a
Press Drop,
in inches
of Hg2
300 to 0.05.
300 to 0.1.
63.3 to 25.2
300 to 0.65.
1 The additive passed the Water tolerance test in both fuels.
9 Total time for the test was 300 minutes; where a pressure drop of 25
inches of mercury occurred before 300 minutes had elapsed, the run eas
stopped to remove the ?lter and then continued to 300 minutes.
45 ‘atoms.
2. The composition of claim 1 containing ‘an antistatic
quantity of from 0.5 to 15.0 lbs. of said betaine per 1000
barrels of said liquid hydrocarbon.
3. A liquid hydrocarbon boiling in the distillate fuel
range containing an antistatic quantity of from 0.1 to
30.0 pounds per 1000 barrels of said liquid hydrocarbon
of a hydrocarbon-soluble betaine of the formula
The pressure drop across the ?lter and the condition
of the preheater tube after 300 minutes with respect to
tube deposits are a measure of the fuels high temperature
stabiltiy. The betaine reduced the preheater tube de~ 60 wherein x is an integer within the range of 0 to 1, R is an
aliphatic hydrocarbon radical, R1 is a saturated divalent
posits formed with both fuels. It improved the ?lter
hydrocarbon radical, and R2 and R3 are saturated aliphatic
ability of the less stable fuel (G) and did not signi?~
hydrocarbon radicals, said betaine containing from about
cantly depreciate the ?lterability of the more stable fuel
As stated, none of the betaine additives, in any of the 65
hydrocarbon compositions described above, promoted
the emulsi?cation of hydrocarbon with water, as deter
mined by the water tolerance test.
The non-emulsifying effect of the subject betaines is
also shown in the following example.
Example 7
The data below show the eifect of N-lauryl betaine
11 to about 35 carbon atoms.
4. The composition of claim 3 wherein the liquid hy
drocarbon contains from 0.5 to 15.0 lbs. of said betaine
per 1000 barrels of said liquid hydrocarbon.
5. A jet fuel liquid hydrocarbon boiling in the distillate
fuel range containing from 0.1 to 30.0 lbs. per 1000 bar
rels of said jet fuel of N-lauryl-N,N~dimcthyl glycine.
6. The composition of claim 5 containing an antistatic
quantity of from 0.5 ‘to 15.0 lbs. of said betaine per 1000
barrels of said liquid hydrocarbon.
7. As an antistatic additive for liquid hydrocarbons
on the interfaeial tension between jet fuels B and G
(JP-5. and iP-4) and water. The measurements were 75 boiling in the distillate fuel range, (1) a liquid hydro
carbon carrier and (2) from 20~60% by weight of said
carrier of ‘a hydrocarbon-soluble betaine of the formula
R _1I\T+_R _COA_
' ‘
betaine containing from about 11 to about 35 carbon
8. The additive of claim 7 wherein the liquid hydro
carbon carrier is xylene.
wherein R1 is a saturated divalent hydrocarbon radical,
R2 and R3 are saturated aliphatic hydrocarbon radicals,
9. The additive of claim 7 wherein the liquid hydrocar
bon carrier is kerosene.
References Cited in the ?le of this patent
and R4 is an uncharged ‘aliphatic radical taken from the
group consisting of hydrocarbon radicals and ether oxy- 10
gen-, hydroxyl-, and carbonyl-substituted hydrocarbon
radicals, R4 being free of substituents that promote the
emulsi?cation of said liquid hydrocarbon with Water, said
Downing et a1. ________ __ Sept. 6,
Stayner et a1. ________ __ Dec. 211,
Vitaiis ______________ __ May 12,
McDermott ___________ __ Sept. 6,
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